The synthesis and microbiological activity of a series of 5-methyl-2-(p-substituted phenyl)benzoxazoles 7a-7g are described. The in vitro microbiological activity of these compounds was determined against some Gram-positive and Gram-negative bacteria and C albicans. The observed minimum inhibitory concentration (MIC) values of the derivatives were compared to some other 2,5-disubstituted benzoxazoles and clinically used drugs. The in vitro microbiological data showed that the derivatives 7a-7g exhibited a broad spectrum of antibacterial activity and 7a-c and 7g were significantly active against E coli and/or K pneumoniae at an MIC of 6.2 μg/ml. © 1990.